Automatic end fastener for film spool



June 6, 1967 B. MOUISSIE 3,

AUTOMATIC END FASTI QNER FOR FILM SPOOL I Filed 06th 18, 1965 FIG. 4

FIG. 6'

-FIG. 5'

INVENTOR 30B Woo/ 5 BY w M ATTORNEY United States Patent 3,323,746AUTOMATIC END FASTENER FOR'FILM SPOOL Bob Monissie, Yverdon,Switzerland,assignor to Paillard A., Sainte-Croix, Vaud, Switzerland, acorporation of Switzerland Filed Oct. 18,1965, Ser. No. 496,783 Claimspriority, application SwitzerlantLFeb. 18, 1965,

2,247/ 65 j, 6 Claims."(Cl. 24274.2)

Film spools are already known, chiefly spools carry ing akinematographic film, which include a hub, two flanges and partsprojecting elastically with reference to the inner surfaces of saidflanges and extending between the hub and the periphery of the spool.Said elastic parts are adapted to clamp the free end of the film, so asto allow winding the latter around the spool. In'order to ensure such aclamping, the film has to be positioned manually over the spool.

The object of the present invention is to allow an automatic securing ofthe film round the spool without any manual operation, which is ofcourse 'of considerable advantage, chiefly in the case ofkinematographic projectors provided with an automatic arrangement forthe positioning of the film. As a matter of fact, in such projectors,channels guide the film so as to make it pass from its feeding meansinto registry with the projection gate, but the operator is generallyconstrained to anchor by hand the film on the take up spool.

My improved spool distinguishes with reference to the above-mentionedknown spools through the fact that the elastic parts carried by oneflange are-angularly shifted with reference to the corresponding partson the other flange.

The accompanying drawing illustrates diagrammatically and by way ofexample a preferred embodiment of my invention.

In said drawings:

FIG. 1 is a side view of one-half the spool, partly in section throughthe hub thereof,

FIG. 2 illustrates thecomplete spool as it would appear viewed in thedirection of the arrow A of said FIG. 1,

FIG. 3 is a sectional view of a part of the spool,

FIG. 4 is a parti-al'side view on a larger scale of a detail of thespool,

FIGS. 5 to 9 illustrate the operation of said spool.

Turning to FIGS. 1 and 2, the spool illustrated includes two flanges 1and 2 located to either side of a hub 3. Each flange is provided with anaxial opening 4 along the periphery of which are cut radial notches 5through which the spool can be fitted over a driving shaft provided withradial projections corresponding thereto, wherethrough the spool may bedriven into rotation by said shaft.

Each flange shows on its inner surface six grooves 6 terminating nearthe periphery of the flange with :a port 7 communicating with a groove 8formed on the outer surface of said flange. The hub 3 is provided withshort longitudinal slots 9 which allow the passage through them ofelongated members or rods 10 forming parts projecting elastically overthe inner surface of the flange. Said rods 10 terminate each with a bentend 11, which end engages the corresponding port 7, whereby a pivotalconnection is obtained for said rod adjacent the periphery of theflange. The inner end of the rod 10 is elastically urged towards themedial plane of the spool, by a spring constituted by a resilient tongue12 cut out of a sheet steel disc 13 extending over the central sectionof the flange considered within the area of the hub 3. Thus, the rods 10are shifted gradually away from the flange as they are considered nearerthe center of the spool. As illustrated in FIG. 1,

the rods 10 carried by one of the flanges 1 are angularly shifted withreference to the rods 10' of the other flange 2 which arediagrammatically shown in FIG. 1 by the superimposed broken lines 10.Furthermore, the inner ends of said rods 10 and 10' extend in adirection passing outside the spool axis and not through the center axisof said opening 4. Through such an arrangement, an excellent clamping ofthe film is obtained when the latter is fitted between the two flanges 1and 2, said clamping action increasing for the portion of the filmnearest the hub.

By reason of the angular shifting or staggered disposition between eachpair of opposed rods 10 and 10' on the two flanges and also by reason ofthe oblique arrangement of each rod with reference to a radialdirection, the film is clamped throughout between a rod 10 or 10' and aportion of flat surface of the flange 2 or 1, respectively, op-

posed that carrying the rod considered. Consequently, if

the film is subjected to a tensioning which has a tendency to modify itsslope at the point at which it is clamped by one of said parts, a nonnegligible friction appears along the film edge which is urged along thecorresponding flange so as to oppose its movement.

FIGS. 5 to 9 illustrate the movements of the film while it is beinganchored automatically on the spool. It should first be remembered thaton a projector, the take-up spool is driven through the agency of afriction coupling and that, in the absence of any slip in said coupling,the tangential speed of the hub of the spool is higher than the speed atwhich the film is fed to the spool.

FIG. 5 shows the introduction of the film F at a speed V between theflanges of a spool which is driven into ro tation and of which thetangential speed V is larger than V The film F passes out of a guidingchannel which is not illustrated and its rigidity is suflicient for itto engage the gap between the flanges of the spool without any furtherguiding means being required.

By reason of the rotation of the spool, the film F engages first a rodsuch as 10 which provides a slight elastic clamping of the end of thefilm. As the spool rotates and the film continues its travel, it engagesin succession each opposed pair of rods 10 and 10' located in staggeredalternation on the inner surface of each of the flanges 1 and 2.

FIGS. 6 to 8 illustrate the gradual Winding of the film round the hub ofthe spool. As soon as the film has reached the position illustrated inFIG. 8, the traction to which it is subjected as a consequence of thetorque acting on the spool and of the clamping of the film by the rods10 and 10 produces a centripetal force which urges the film towards thehub 3. Since the film slides with reference to the pressure-exertingrods by reason of the difference between the speed of the spool and thespeed of progression of the film, the end of the film which wascomparatively far from the hub 3 is urged gradually towards the latter.As a matter of fact and as a consequence of the film bearing against oneof the flanges of the spool in registry with each rod 10 or 10 engagingone edge of the film, there arises, as already mentioned hereinabove, anon-negligible resistance opposing a change in the angular setting ofthe film at the point at which it is clamped. Thus, the point a in FIG.8 shows the location at which a pressure is exerted on the film by a rod10. Said rod moves clockwise quicker than the film and the point a showsin FIG. 9 that point very near the extreme end portion of the film wherethe greatest pressure is exerted upon the film. It is thus apparent thatthis extreme portion of the film is speedily led towards the hub so asto be finally engaged in contacting relationship therewith. As soon asthe film has executed more than one convolution round the hub, a selfclamping of the film is obtained and the film is thus held fastenergetically against the spool hub.

Obviously, numerous modifications may be brought to the spool described,the chief feature consisting in that the elastic parts of one flange areangularly shifted with refer- V ence to the parts of the other flange.In the case of flanges formed by steel sheets, the springs acting on theends of the rods may be constituted readily by tongues cut in the metalsheet-s forming the flanges. In a simpler structure, the elastic rodsmay also be constituted by tongues cut in the steel sheets forming theflanges.

In the embodiment described, the two flanges were similar which is of aconsiderable advantage from the standpoint of manufacture, but obviouslysuch a symmetry is not essential and also the number of rods provided oneach flange may be modified, although it is preferable to use at leastthree rods on each flange.

What I claim is:

1. A spool, chiefly for kinematographic films, comprising a hub, twoparallel flanges carried by said hub, two series of elongated membersprojecting inwardly from the inner surface of the corresponding flangeand extending between the hub and the outer periphery of said flanges,means within said hub engaging the free inner ends of said members onboth of said flanges to elastically urge the inner ends of said memberstowards the medial plane of said spool, said means yieldable against anoutside force to permit outward displacement of the inner I ends of saidmembers, and the inner ends of one series of members on one of saidflanges being disposed in staggered angular relationship to the innerends of the other series of members on the other one of saidrflanges.

2. A spool, chiefly for kinematographic films, comprising a hub, twoparallel flanges carried by said hub, two series of elongated members onthe inner surface of said flanges, each member forming an angle with aradius of the flange carrying it, which is different from the angleformed by the corresponding member carried by the flange opposed to thelast mentioned flange with said radius, said members projecting over theinner surfaces of the corresponding flanges and extending between thehub and the outer periphery of said flanges, means between said flangesspring urging the inner ends of said members towards the medial plane ofsaid spool, and said members caried by one of said flanges beingdisposed in staggered relationship 7 with those members carried by theother of said flanges;

3. A spool, chiefly for kinematographic films, comprising a hub, twoparallel flanges carried by said hub and two series of elongated memberspivotally connected to each of the corresponding flanges at pointsdistributed adjacent the periphery of the latter, said elongated membersextending over the surfaces of said corresponding flanges with agradually increasing spacing with reference to the latter towards thehub, and spring means located adjacent the hub and urging the differentmembers elastically away from the portion of the corresponding flangeadjacent the hub, and the members carried by one flange being out oftransverse registry with those carried by the other flange.

4. A spool according to claim 1, wherein said two parallel flanges areof similar construction and are attached to said hub in a radiallydisplaced relationship to provide said staggered arrangement of theinner ends of said opposed members.

5. A spool, chiefly for kinematographic films, comprising a hub, a'pairof flanges carried by said hub, two parallel disc elements carried bysaid hub, a plurality of incurved tongues cut out of the peripheralportions of said discs, and two series of elongated members pivotallyconnected to each of the corresponding flanges at points distributedadjacent the periphery of the latter, said members extending over thesurfaces of said corresponding flanges with a gradually increasingspacing with reference to the latter towards said hub, said membersbeing urged elastically away from the portion of the correspondingflange adjacent the hub by said tongues cut out of said disc elements. It

6. A spool, chiefly for kinematographic films, comprising a hub, twoparallel flanges carried by said hub, two series of film-clamping rodsrespectively carried by said flanges, each film-clamping rod forming anangle with a radius of the flange carrying it, which is different fromthe angle formed by the corresponding film-clamping rod carried by theflange opposed to the last-mentioned flange with said radius, saidfilm-clamping rods projecting elastically over the inner surfaces of thecorresponding flanges and extending between the hub and the outerperiphery of said flanges, the film-clamping rods carried by one flangebeing out of transverse registry with those opposed rods carried by theother flange.

References Cited UNITED STATES PATENTS 1,861,882 6/1932 ,Ross 24274.21,861,891 6/1932 Wittel 24274.2 2,004,608 6/;1935 Howell 24274.2

FRANK J. COHEN, Primary Examiner.

N. L. MINTZ, Assistant Examiner.

